Restoring the Temple – The Urinary System

“And God opened her eyes, and she saw a well of water; and she went, and filled the bottle with water, and gave the lad drink.”                           —Genesis 21:19.

When Hagar was wandering in the wilderness of Beersheba with her son, she ran out of water.  Abraham had given her bread and water as they set out, but now the water was gone.  The bread may have been gone as well, but when it looked like death was imminent, God gave them water with which they revived.  Humans can go many days, even weeks, without food, but without water, we will die in a few short days.  The urinary system works closely with water in order to keep us healthy.

The urinary system consists of two kidneys, two ureters (tubes from the kidneys to the bladder), the bladder, and the urethra (the tube that goes from the bladder to the outside of the body).  The purpose of the urinary system is to remove excess fluid and other substances from the body and filter out waste products from the blood.  As we learned last month, the body processes the food we eat and extracts the nutrients to “feed” every cell in the body.  The waste products left over go into the blood stream.  If this waste is not removed from the body, you will die.  There are several organs that help remove waste from the body, including the skin, lungs, and intestines.  These other body systems work alongside the urinary tract system in keeping chemicals and water in balance.

Each kidney is shaped similar to a kidney bean and is about the size of a computer mouse.  They are placed in the rear of the abdominal cavity, just below the ribs.  The kidneys contain tiny filtering units called nephrons (there are about a million of these in each kidney).  Each of these units consists of a small round collection of blood capillaries and a small tube called a renal tubule.  Here is what happens.  The blood, full of excess water and waste products, passes into a kidney.  Now the blood is traveling through the tiny capillaries in the nephrons.  The excess water, waste, and other unneeded chemicals cross the extremely thin wall of the capillary and into the renal tubule.  This waste and water is called urine, and it then travels from the tubules and out of the kidney via the ureters which are about 8–10 inches (20–25 cm) long in an adult.  Gravity helps urine travel from the kidneys to the bladder, but muscles in the ureter walls also help force the urine in a one-way direction.  Small amounts of urine drip into the bladder about every 10 to 15 seconds.  About 440 gallons (1,665 liters) of blood are filtered through the kidneys each day.

The bladder is a hollow muscular organ that sits in your pelvis.  The purpose of the bladder is to store urine until you are ready to dispose of it.  As urine fills it up, the bladder gets larger and then shrinks back down when drained.  The bladder can comfortably hold about 2 cups (16 ounces) of urine for a few hours.  It is most healthy, however, to empty your bladder as soon as you feel the urge.

Circular muscles located at the bladder exit keep the urine from leaking out.  These sphincter muscles close tightly, keeping the fluid from flowing down the urethra.  As your bladder fills, nerves from the bladder signal the brain that you need to urinate.  As you urinate, the bladder muscles contract and the sphincter muscles relax.  Urine exits the bladder, travels down the urethra and out of the body.

Kidneys are very important. You need at least one kidney to live.  There are many factors that can cause the urinary system to have problems.  As we age, our muscles lose strength and sometimes a person finds they “leak” more easily, especially when coughing or sneezing.  Urinary tract infections occur when bacteria travel up the urethra and into the bladder, or all the way up the ureters and into the kidneys.  An injury or illness may prevent the kidneys from filtering the blood properly or blocking the passage of urine.  As with all systems of the body, it is essential to have healthy eating habits and drink plenty of fluid.  Ellen White stated that, “Catarrhal difficulties [colds], kidney disease, headache, and heart troubles are the result of immoderate eating.”  Healthful Living, 176.  It may seem logical that the more water you drink, the harder the kidneys have to work, and therefore they will wear out sooner.  In fact, the opposite is true.  The less you drink, the less fluid circulates through your bloodstream.  The body’s cells are still producing the same amount of waste, which is dumped into the blood.  This blood, chock full of waste products, circulates as usual through the kidneys, which have to work harder to filter the blood, and consequently produce darker, concentrated urine.  Dehydration will therefore help to wear out the kidneys faster, not to mention what keeping all that concentrated waste around in your blood will do to the rest of your body!  Most people do not drink enough fluids and are walking about in a state of constant dehydration.  Bottom line: drink lots of fluids, especially pure water, to help keep your kidneys and entire body in optimum working order, as God intended.

“O God, thou [art] my God; early will I seek thee: my soul thirsteth for thee, my flesh longeth for thee in a dry and thirsty land, where no water is.” Psalm 63:1.

Sheryle Beaudry, a certified teletriage nurse, writes from Estacada, Oregon where she lives with her husband and twin daughters.  She may be contacted by e-mail at